In august I will go to Japan to visit relatives and to make a trekking. In europe I usualy bring trekking meals with me, the kind of meals that you can easily prepare on a stove by just adding water.

Those meals are sealed in plastic and usually look like this:

I've never had any problems in Europe, but when I look up the regulations on traveling to Japan, I read various restriction, ranging from not being allowed to bring in any meat products, up onto dissolowence of milk, vegetable or egg products.

I could live without meat (there are vegetarian meals available), but the other ingredients would be a problem.

2 Answers
2

No meat products can be brought into Japan without the inspection
certificate.

This requirements applies to any import irrespective of the use or
quantity: it should be noted that import of such products for
souvenir, personal consumption or commercial sample, no matter how
small the quantity is, needs to obtain an inspection certificate
issued by the government authority.

Regarding beef or beef offal exported from Canada, U.S.A., France, The
Netherlands or Ireland to Japan, only these commodities treated in
accordance with the animal health requirements ... including specific
export programs and designation of facilities, are acceptable.

Furthermore, it is to be noted that beef products (e.g. ham, sausage,
beef jerky) have not been allowed to be imported.

So that's the legal theory. In practice, Customs is much more interested in drugs, large amounts of alcohol etc. If they do spot that you've got meat, it will be confiscated and destroyed, but I've never heard of anybody being fined or worse.

Non-meat foods, on the other hand, despite what the regulations may say, are totally OK in practice. Eggs and milk that are obviously processed are not a problem at all, I (and every single Japanese tourist ever) bring in baked goods every time I visit (curse you, omiyage!) and I have never had a problem. Fresh food (fruits etc) has some restrictions, but they're not relevant to you.

All that said, bringing food all the way from Europe seems a bit pointless, trekking is extremely popular in Japan and any camping goods store will have a huge selection of portable "just-add-water" foods. Here are the selections at two random online shops: Sports Authority, Kojitsu Sanso.

Bringing that product shouldn't be a problem at all. I brought oats and other packaged food- no problem at all. There are very few restrictions- only plants are restricted materials and then they are only concerned with non-commercial products.